Vehicle occupant restraint belt systems conventionally include at least one belt portion and a buckle for detachably securing a keeper of the belt system to secure the belt portion across the occupant so as to restrain the occupant from movement. The buckle normally includes a hollow housing in which a latch member is received for movement between latched and unlatched positions to detachably secure the keeper. Currently manufactured restraint belt systems for the most part have the keeper constructed with a D-shape and are thus referred to as a D-ring. The latch member is received within the opening of the D-shaped keeper to secure the keeper to the buckle in a latched position and is moveable from the latched positioned to an unlatched position to release the keeper from the buckle and thereby free the occupant from the restraint belt system. Conventional vehicle occupant restraint systems of this type are disclosed by U.S. Pat. Nos. 4,052,775 Gavagan et al and 4,064,603 Romanzi, Jr.
In order to ensure that the vehicle occupant restraint belt system is utilized, prior systems have incorporated indicators such as disclosed by U.S. Pat. No. 3,588,811 Prickett to provide a light indication at the instrument panel of the securement of the keeper by the buckle. Likewise, as disclosed by U.S. Pat. Nos. 3,806,867 Quantz and 3,934,671 Hart, vehicles have also utilized ignition interlocks, with or without a warning device, to prevent vehicle operation when the restraint belt system is not in place with the keeper secured by the buckle.
Prior vehicle restraint belt systems such as disclosed by U.S. Pat. No. 4,365,285 Brundidge have also included an illuminated clip which attaches to one end of the belt and is illuminated by a fiber optic cord from a remote light source when the buckle and the keeper are in a detached relationship from each other. Upon securement of the keeper by the buckle, a switch is open circuited such that the remote light source is extinguished and the illumination by the clip is likewise extinguished. Provision of this illumination clip and the associated fiber optic cord for lighting the clip for a remote source is not a particularly efficient arrangement for providing illumination of the buckle.
Other prior art references which were noted during the investigation conducted for the present invention but which relate to non-analogous art such as jewelry illumination and lighted night belts are disclosed by U.S. Pat. Nos.: 2,854,563 Catching; 3,549,878 Bailey; 3,840,853 Cukale; 4,009,381 Schreiber et al; 4,112,482 Powell; 4,186,425 Nadimi; and 4,283,756 Beamon.